PROJECT SUMMARY: Clinical research must enroll individuals from diverse backgrounds to yield generalizable knowledge and ensure that the benefits and burdens of research are fairly distributed. Under- representation of diverse groups may: (1) lead to poor enrollment leading to delays and/or study failure, (2) prevent diverse groups from experiencing the benefits of research and (3) result in investigators missing important diversity based differences in illness and treatment. The pediatric literature has not produced consensus regarding under/over enrollment of diverse groups in research and there is inadequate understanding as to why disparities may exist. Enrollment in emergency and critical care (ECC) settings presents unique challenges. These factors, coupled with knowledge that health outcomes are strongly tied to evidence supporting medical interventions, motivate the proposed research. The goal of this proposal is to characterize research participation by children at risk for health disparities (CRHDs) in pediatric ECC research and to determine the degree to which modifiable and potentially modifiable factors relate to participation. The central hypothesis?that CRHDs are underrepresented (losing research benefit) and overrepresented (risking exploitation) in others and that modifiable factors are the primary drivers of differential study enrollment?will be evaluated in a mixed-methods study with 3 interrelated but distinct aims: Aim 1: To prospectively characterize enrollment by CRHDs in pediatric ECC research and to identify factors associated with enrollment and retention. Aim 2: To elucidate qualitative insights into modifiable and non-modifiable factors impacting enrollment/retention in pediatric ECC research. Aim 3: To determine which factors are most associated with successful enrollment of CRHDs. Aim 1 will be addressed through prospective tracking of study enrollment/retention data in an anticipated 18 studies at a single site and factors associated with enrollment. Aim 2 will be accomplished through semi-structured interviews of parents and study team staff. Aim 3 combines prospective survey and interview methods to develop a priority order for the most important factors related to parental decisions to participate to plan future intervention studies. This project will advance the candidate?s long-term goal to engage in interdisciplinary research and policy development using evidence-based, stakeholder-informed, and ethically-sensitive practices to reduce health disparities, address bias, and promote health equity for children. Mentors with expertise in pediatric ethics, disparities, clinical trials, decision-making, and health communication augmented by essential institutional support will permit the candidate to expand knowledge of research methods relevant to decision- making, develop expertise in health disparities research, and cultivate dissemination and implementation skills to effectively improve the evidence base relied upon to treat the sickest children. The proposed plan is instrumental to a successful transition to independence and becoming a leader in the field.